Cross-bridge x-ray machine.



P. BERLIN.

CROSS BRIDGE X-RAY MACHINE.

APPLICATION FILED IULY 14. I916.

(InucHIo:

P. BERLIN.

CROSS BRIDGE X-RAY MACHINE.

APPLICATION FILED JULY 14. 1916.

1 ,273,812. Patented July 30, 19m

4 SHEETS-SHET 2.

3mm: mloz Paul Berlin @3313 M Elite L11 P. BERLIN.

CROSS BRIDGE X-RAY MACHINE.

APPLICATION FILED JULY I4. I916.

1 373,81 2. Patented July 30, 1918.

4 SHEETS-SHEET 3.

' Pa a Z Berlin P. BERLIN.

CROSS BRIDGE X-RAY MACHINE.

APPLICATION FILED JULY 14. 1916.

1 ,27 3,8 1 2. Patented July 30, 1918.

4 SHEETS-SHEET 4.

UNITED STATES PATENT OFFICE.

PAUL BERLIN, 0F HoEoKEN', NEW JERSEY, ASSIGNOIR. TO THE KNY-SCHEERER CORPO- RATION, A conron'a'rrou OF NEW YORK,

CBOSS-BRIDGEX-RAY MACHINE. f

To all whom it may concern: Be it known that I, PAUL BERLIN, a citizen of the United States, and a resident of Hoboken, county of Hudson, and State of New Jersey, have invented certain new and useful Improvements in. Cross-Bridge X Ray Machines, set forth in the following specification.

latory electric currents for therapeutic use.

The object of the present invention is to improve and make more reliable the rectifying commutator which forms a necessary part in a machine of the class described. More specifically, the object of this invention is to minimize the difficulties arising from the are drawn out by the rotating parts of a high-potential rectifier. It has been found in practice that trouble is experienced from what is believed to be ionized particles of a conducting character which collect or persist in a position'or path to form a continuing conducting path after an'interruption in the circuit'is desired, provided there is present any part of themechanism (even though the same be of an insulating character) which will form a carrier or path former for the said particles. It is believed that centrifugal and centripetal forces and also the force governing charged particles control the action of the ionized particles which give the trouble mentioned. A specific object of this invention is to design the rectifier in such a way that these various forces will tend to act in opposition one to another and result in a quick disruption of the undesired arc. A further and more specific obJect of the invention is to design the apparatus so that a single insulating plate in the commutator structure will serve the double purpose of effecting revolution of rectifying conductors and also serve as a positive lnsulating barrier between stationary parts of the rectifying mechanism.

The above will be better understood by reference to the illustrative embodiments of the invention described and claimed herein in connection with the accom anying drawings which form a part hereo in which like characters designate corresponding parts in Specification of Letters Patent.

Patented July 30, 1918.

Application filedJ'uly 14, 1916. Serial No. 109,251.

the several figures and in which Figure 1 is a front elevation of an X-ray machine embodying the invention, with the doors removed; Fig. 2 is a vertical section with parts shown in elevation along the line IIII of Fig. 1; Fig. 3 is a still further enlarged detail section, with parts broken away, through line III-III of Fig. 2; Fig. 4 is a section,

with parts broken away, through line IV-IV of Fig. 3; Fig. 5 is a perspective view showing a modified form of the rotating part of the rectifier; Fig. 6 is a diagrammatic view showing a rectifier which evidences in practice the arcing trouble which it is an object of this invention to overcome; and Fig. 7 is a diagrammatic illustration showing the circuit connections in the present invention.

It is customary in machines of this character to employ an inverted rotary converter if direct current is the original source of supply, but to employ a synchronous motor if alternating current is the source of supply. If the synchronous motor is employed, both the motor and the primary of the step-up transformer are connected directly to the source. If an inverted rotary converter is employed the alternating current windings are connected to the primary of the step-up transformer. The expression motor element having alternating current windings is therefore employed to designate generically both the inverted rotary converter or a synchronous motor or its equivalent. The purpose of this interconnection between the circuits to be rectified and the motor element would of course be understood as to maintain synchronism between the rotating rectifier and the current wave to be rectified.

In the drawings, a suitable cabinet A is provided to contain the various pieces of mechanism in a manner well understood in the art. B is a step-up, high-potential trans former and C is the electric machine comrising the motor element having alternatmg current windings. D is the rectifyin mechanism proper. The high-potentialeads from the secondary of the transformer .B are indicated by 1 and 2, while the de- 1 and 2 is alternating from plus to minus and from minus to plus while it is desired that the leads 5 and 6 be respectively at all times either plus for '5 and minus for '6' or vice versa. The supporting frame 7 shown substantially square in construction, serves to mount the stationary conducting parts of the rectifier and may be'of wood.

A pair of diametrically opposed receiving arcs 8 and 9 are suitably insulated and mounted by insulators 10 and 11 in the frame 7, preferably so that one is vertically above the other, are 8 being connected to lead 1 and are 9 being connected to lead 2. Intermediate the arcs 8 and 9 but axially separated therefrom is another pair of diametrically opposed conducting arcs 12 and 13 similarly insulated from and supported by the frame 7 through the medium of insulators 14: and 15, are 12 being connected to.

delivery lead 5 and are 13 being connectedto delivery lead 6. In other words, the pairs of arcs 8-9 and 12--13 occupy respectively parallel planes, which planes are spaced apart axially along the imaginary axis passing through the centers of the circles of which the arcs form parts. It is preferable that, when viewed axially, the arcs overlap one another slightly, as best shown in Fig. 2, although this overlapping is not essential and may vary in'degree. Thus each arc must be of an extent at least approximately 180 electrical degrees which, for the type of generator illustrated, necessitates an arc of at least approximately 90 mechanical degrees. 'The more the overlap of the arcs, that is, the more their extent greater than 90 mechanical degrees is, the greater is the portion of the current wave delivered to the X-ray tube. Approximately the middle of the overlapping portions of the arcs represents the peak of the current wave. The extent of each current Wave delivered to the X-ray tube in electrical degrees is twice'the number of mechanical degrees of arc-overlap plus twice the number of mechanical degrees beyond and before the overlap throughout which an effective cross-connection is maintained by the high tension are which flows even when there is no overlap.

The shaft 16 from the motor element C is arranged axially of the arcs 8, 9, 12 and 13 and carries fixedly a rotary element 17 secured thereto by adjustable coupling 18. In Figs. 1, 2, 3, 4 and 7 this rotary element is an extensive insulating plate preferably in the form of a disk of mica board and of'an extent to lap radially out a considerable extent be-.

yond the radial extent of the ares 8, 9, 12 1 and 13 so as to form a continuous insulating partition between the receiving arcs and the delivery arcs. By this means the insulating air gap between the axially separated arcs of opposite electrical sign is materially lengthened :without axially increasing the separation of the arcs. In other words, by this means, the axially separated arcs may be located quite close to each other without danger shaft 16 when the disk 17 is rotated syn-' chronously with the motor element. In this manner the receiving are 9 is bridged, for example, to the delivery are 12 when the receiving are 9 is plus At the same time the receiving are 8 is bridged to the delivery arc 13 when the receiving are 8 isminus \Vhen the sign of the receiving are 8 is changed to plus the cross-conductor is in position to connect it to the delivery are 12 and at this time the then minus receiving arc, 9 is connected to the delivery are 13. It should be noted that these cross conductors are not alined with the conducting aros The radius of thepath' of revolution of the cross conductors should preferably be not the same as the radius of the conducting arcs; in the drawings it is shown to be materially less.

transformer B is to be understood as connected in circuit with the leads 26 of the motor element. The secondary 27 of transformer B'has its plus-minus (i) lead 1 in connection with the are 8 and its minus-plus F) lead 2 connected with the arc 9. The delivery leads 5 and 6 are connected respec tively with the arcs 12 and 13. In the position of the mechanism shown, the crossconductor 19 is cross-connecting receiving are 8 to the delivery are 13 and cross-conductor 20 is connecting receiving are 9 to delivery are 12. A 90 revolution of the cross-conductor 20 to the position shown by the dotted circle 30- will cause the then minus receiving arc 8 to be connected to the delivery arc 12 while the cross-conductor 19 has moved to the position 29 to cross-connect arcs 9 and 13 instead of 8 and 13. c

It is, of course, to be understood .that in high-potential rectification it is not neces--- sary that the moving conductors of the rectifier physically contact with the stationary conductors of the rectifier, although physical contact may take place through the me- .dium of flexible brushes. Satisfactory rectirated one from another and preferably on opposite sides of the mica board disk. Any are which is pulled out atthe time'a crossconductor leaves a stationary conductor is subjected to a force tending to divert it and any ionized particles contained therein from the rotating arts of the apparatus. This is radically di erent from the action in appa-' ratus such as shown in Fig. 6 in which an are broken between the rotating conducting are 31 and a stationary conductor 32 tends to sweep around the peri hery 38 of the disk 33. It has been found t at the ionized particles cling to this supposedly insulating surface and maintain the circuit indefinitely so that rectification is impossible. In Fig. 5 is illustrated a modified structure in which a hub 40 is adjustably secured to the shaft 16 and carries cross-conductors 41 and 42 connected to insulating spokes 43 and In other words, the disk 17 is omitted, whereas many of the advantages of the present invention are retained. The relative positioning of the cross-conductors. 41 and 42 is the same as the positioningof the cross-conductors 19 and 20 with relation to the stationary arcs, and the circuit connec' tions will of course remain the same.

. The detail construction for the preferred form andmountin of the cross conductors 19 and 20 is shown in detail for the are 19 in Figs. 3 and 4. Each cross-conductor comprises a central threaded stub 50 and two reduced end sides of the ing equi-distantly out therefrom. The extensions 51 and 52 are preferably oval in cross-section to reduce windage. Lock-nuts 53, 51, 55 and 56 firmly lock the cross-con-' ductor to the disk 17 and readily'permit lengthwise adjustment of the same relatively to the disk 17. p

What is claimed and what is desired to be secured by United States Letters Patent 1s 1. In a high potential converting mechanism, a motor-element having. alternating current windings; a pair of insulated diametrically opposed revoluble cross-conductors extensive in a direction parallel to their axis of revolution and of limited. extent in their path of revolution; a pair of diametrically opposed insulated receiving arcs each spanning approximately at least 90 mechanical degrees and cooperable with the receiving ends of. said cross-conductors; means for revolving said cross-conductors synchronously with said motor element comprising a plate of insulating material exortions 51 and 52 on opposite isk 17 and preferably extend-.

tending cross-wise to each conductor, in ex- .tent approximating atleast one-half the length of said cross-conductor; a step-up transformer having a primary coil adapted to be connected in circuit with the alternating current windings of said motor-element and having a high-potential secondary coil in circuit with said receiving arcs; and a pair of diametrically opposed insulated delivery arcs intermediate and axially spaced out of the plane of said receiving arcs each spanning approximately at least 90 mechanical degrees and in cooperable relation with the delivery ends of said cross-conductors, 4

whereby said cross-conductors operatively cross-connect said receiving arcs with said deliveryv arcs synchronously with the alternating wave in a manner to cause a nonalternating current to be available from said delivery arcswhen the apparatus is energized from a suitable source of electric energy. p

2.. In a high-potential convertingmechanism, a motor-element having alternating current windings; a pair of insulated dia-- metrically opposed revoluble cross-conductors extensive in a direction parallel to their axls of revolution and of limitedextent in their path of revolution; means for revolving said cross-conductors synchronously with said motor-element, comprising an extenslve lnsulatlng plate extending radially beyond said cross-conductors an amount approximating at least ,one-half of the length of a cross-conductor; a pair of diametrically opposed insulated receiving arcs cooper able with the receiving ends of said cros' conductors; a step-up transformer having a primary coil adapted to be connected in cir with the delivery ends of said cross-conductors, whereby-said cross-conductors operatively cross-connect said receiving arcs with said delivery arcs synchronously with the al ternatlng wave in a manner to cause a nonalternating current to be available from said delivery arcs when the apparatus is energized from a suitable source of electric energy. 7

3. A high-potential rectifier comprising an insulating plate mounted to rotate on a central axis at right angles to the plane of said plate; a pair'of diametrically A opposed cross-conductors secured to and extending through said plate at positions a material distance radially inward from the rim of said plate approximating at least one-half of the length of'a cross-conductor;

a pair of diametrically opposed insulated receiving arcs mounted opposite one face of the path of travel of the delivery ends of said cross-conductors.

4. A high-potential rectifier comprising an insulating disk mounted to rotate on a central axis at right angles to the plane of said disk; a pair of diametrically opposed cross-conductors secured to and extending through said disk; a pair of diametrically opposed insulated receivin arcs mounted opposite one face'of said disk adjacent to the path of travel'of the receiving ends of said cross-conductors; and a pair of diametrically opposed insulated delivery arcs mounted opposite the other face of said disk intermediate the position of. said receiving arcs and adjacent the path of travel of the delivery ends of'said cross-conductors, said arcs being located a material distance approximating at least one-half of the length of a cross-conductor toward the center from the periphery of said disk.

5. In a high-potential rectifier for X-ray machines, two sets of conducting arcs occupying respectively displaced parallel planes; a rotatable member the rim portion of which, extending radially both outwardly and inwardly a material distance approximating at least one-half of the length of a cross-conductor beyond the radial position of saidv conducting arcs, is formed of sheet insulating material; and cross conductors extending through said rim of sheet insulating material, and mechanically attached thereto in cooperable relation with said conducting arcs.

6. In a high-potential rectifier for X-ray machines, two sets of conducting arcs occupying respectively displaced parallel planes; a rotatable member the rim portion of which, extending radially both outwardly and inwardly a material distance approximating at least one-half of the length of a cross-conductor beyond the radial position of said conducting arcs, is formed of sheet 1 alinement with extending through said rim of sheet insulating material, and mechanically attached thereto in cooperable relation with said conducting arcs, but out of alinement with said conducting arcs, whereby. Warping of said sheet material cannot cause a collision between a cross conductor and a conducting arc.

7. In a high-potential rectifier for X-ray machines, two sets of conducting arcs occupying "respectively displaced parallel planes; a rotatable member the rim portion of which, extending radially both outwardly and inwardly a material distance beyond the radial position of said conducting arcs, is formed of sheet insulatin material; and cross conductors extending t rough saidrim of sheet insulating material, and mechanically attached thereto in cooperable relation with said conducting'arcsg'each cross 0011- ductor comprisin a centrally threaded portion projecting through said rim and having clamping nuts on opposite sides of said rim whereby an adjustment in both directions of its length may be effected.

8. In a high-potential rectifying switch for X-ray machines a cross conductor comprising a centrally threaded portion having at each end an extension having an air-cleaving configuration and clamping nuts for said threaded central portion.

9. In a high-potential rectifier, two sets of stationary conductin arcs occupying respectively spaced para lel planes; a rotatable member mounted to rotate about the axis of said conducting arcs and comprising a plurality of cross conductors revolving in cooperation with said stationary conducting arcs and a mounting constraining said cross-conductors to occupy positions out of said conducting arcs,

whereby incidental bending or warping of said rotatable member cannot cause a collision between such cross conductors and a conducting are.

In witness whereof I have signed my name to this specification, this 1st day of July, 1916.

PAUL BERLIN. 

